CommandBuffer.SetViewProjectionMatrices

Parameters

Description

Add a command to set the view and projection matrices.

This function is equivalent to calling SetViewMatrix and SetProjectionMatrix. It is slightly more efficient when changing both matrices at once.

Note: The camera space in Unity matches OpenGL convention, so the negative z-axis is the camera's forward. This is different from usual Unity convention, where the camera's forward is the positive z-axis. If you are manually creating the view matrix, for example with an inverse of Matrix4x4.LookAt, you need to scale it by -1 along the z-axis to get a proper view matrix.

using UnityEngine;
using UnityEngine.Rendering;

// Attach this script to a Camera and pick a mesh to render.
// When entering Play mode, this will render a green mesh at
// origin position, via a command buffer.
[RequireComponent(typeof(Camera))]
public class ExampleScript : MonoBehaviour
{
    public Mesh mesh;

    void Start()
    {
        var material = new Material(Shader.Find("Hidden/Internal-Colored"));
        material.SetColor("_Color", Color.green);

        var tr = transform;
        var camera = GetComponent<Camera>();

        // Code below does the same as what camera.worldToCameraMatrix would do. Doing
        // it "manually" here to illustrate how a view matrix is constructed.
        //
        // Matrix that looks from camera's position, along the forward axis.
        var lookMatrix = Matrix4x4.LookAt(tr.position, tr.position + tr.forward, tr.up);
        // Matrix that mirrors along Z axis, to match the camera space convention.
        var scaleMatrix = Matrix4x4.TRS(Vector3.zero, Quaternion.identity, new Vector3(1, 1, -1));
        // Final view matrix is inverse of the LookAt matrix, and then mirrored along Z.
        var viewMatrix = scaleMatrix * lookMatrix.inverse;

        var buffer = new CommandBuffer();
        buffer.SetViewProjectionMatrices(viewMatrix, camera.projectionMatrix);
        buffer.DrawMesh(mesh, Matrix4x4.identity, material);

        camera.AddCommandBuffer(CameraEvent.BeforeSkybox, buffer);
    }
}

See Also: SetViewMatrix, SetProjectionMatrix, Camera.projectionMatrix, Matrix4x4.LookAt, Matrix4x4.Perspective.